1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994 Waldorf GMBH
7  * Copyright (C) 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003 Ralf Baechle
8  * Copyright (C) 1996 Paul M. Antoine
9  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
10  */
11 #ifndef _ASM_PROCESSOR_H
12 #define _ASM_PROCESSOR_H
13 
14 #include <linux/atomic.h>
15 #include <linux/cpumask.h>
16 #include <linux/sizes.h>
17 #include <linux/threads.h>
18 
19 #include <asm/cachectl.h>
20 #include <asm/cpu.h>
21 #include <asm/cpu-info.h>
22 #include <asm/dsemul.h>
23 #include <asm/mipsregs.h>
24 #include <asm/prefetch.h>
25 #include <asm/vdso/processor.h>
26 
27 /*
28  * System setup and hardware flags..
29  */
30 
31 extern unsigned int vced_count, vcei_count;
32 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
33 
34 #ifdef CONFIG_32BIT
35 #ifdef CONFIG_KVM_GUEST
36 /* User space process size is limited to 1GB in KVM Guest Mode */
37 #define TASK_SIZE	0x3fff8000UL
38 #else
39 /*
40  * User space process size: 2GB. This is hardcoded into a few places,
41  * so don't change it unless you know what you are doing.
42  */
43 #define TASK_SIZE	0x80000000UL
44 #endif
45 
46 #define STACK_TOP_MAX	TASK_SIZE
47 
48 #define TASK_IS_32BIT_ADDR 1
49 
50 #endif
51 
52 #ifdef CONFIG_64BIT
53 /*
54  * User space process size: 1TB. This is hardcoded into a few places,
55  * so don't change it unless you know what you are doing.  TASK_SIZE
56  * is limited to 1TB by the R4000 architecture; R10000 and better can
57  * support 16TB; the architectural reserve for future expansion is
58  * 8192EB ...
59  */
60 #define TASK_SIZE32	0x7fff8000UL
61 #ifdef CONFIG_MIPS_VA_BITS_48
62 #define TASK_SIZE64     (0x1UL << ((cpu_data[0].vmbits>48)?48:cpu_data[0].vmbits))
63 #else
64 #define TASK_SIZE64     0x10000000000UL
65 #endif
66 #define TASK_SIZE (test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
67 #define STACK_TOP_MAX	TASK_SIZE64
68 
69 #define TASK_SIZE_OF(tsk)						\
70 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
71 
72 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
73 
74 #endif
75 
76 #define VDSO_RANDOMIZE_SIZE	(TASK_IS_32BIT_ADDR ? SZ_1M : SZ_64M)
77 
78 extern unsigned long mips_stack_top(void);
79 #define STACK_TOP		mips_stack_top()
80 
81 /*
82  * This decides where the kernel will search for a free chunk of vm
83  * space during mmap's.
84  */
85 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
86 
87 
88 #define NUM_FPU_REGS	32
89 
90 #ifdef CONFIG_CPU_HAS_MSA
91 # define FPU_REG_WIDTH	128
92 #else
93 # define FPU_REG_WIDTH	64
94 #endif
95 
96 union fpureg {
97 	__u32	val32[FPU_REG_WIDTH / 32];
98 	__u64	val64[FPU_REG_WIDTH / 64];
99 };
100 
101 #ifdef CONFIG_CPU_LITTLE_ENDIAN
102 # define FPR_IDX(width, idx)	(idx)
103 #else
104 # define FPR_IDX(width, idx)	((idx) ^ ((64 / (width)) - 1))
105 #endif
106 
107 #define BUILD_FPR_ACCESS(width) \
108 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
109 {									\
110 	return fpr->val##width[FPR_IDX(width, idx)];			\
111 }									\
112 									\
113 static inline void set_fpr##width(union fpureg *fpr, unsigned idx,	\
114 				  u##width val)				\
115 {									\
116 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
117 }
118 
119 BUILD_FPR_ACCESS(32)
120 BUILD_FPR_ACCESS(64)
121 
122 /*
123  * It would be nice to add some more fields for emulator statistics,
124  * the additional information is private to the FPU emulator for now.
125  * See arch/mips/include/asm/fpu_emulator.h.
126  */
127 
128 struct mips_fpu_struct {
129 	union fpureg	fpr[NUM_FPU_REGS];
130 	unsigned int	fcr31;
131 	unsigned int	msacsr;
132 };
133 
134 #define NUM_DSP_REGS   6
135 
136 typedef unsigned long dspreg_t;
137 
138 struct mips_dsp_state {
139 	dspreg_t	dspr[NUM_DSP_REGS];
140 	unsigned int	dspcontrol;
141 };
142 
143 #define INIT_CPUMASK { \
144 	{0,} \
145 }
146 
147 struct mips3264_watch_reg_state {
148 	/* The width of watchlo is 32 in a 32 bit kernel and 64 in a
149 	   64 bit kernel.  We use unsigned long as it has the same
150 	   property. */
151 	unsigned long watchlo[NUM_WATCH_REGS];
152 	/* Only the mask and IRW bits from watchhi. */
153 	u16 watchhi[NUM_WATCH_REGS];
154 };
155 
156 union mips_watch_reg_state {
157 	struct mips3264_watch_reg_state mips3264;
158 };
159 
160 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
161 
162 struct octeon_cop2_state {
163 	/* DMFC2 rt, 0x0201 */
164 	unsigned long	cop2_crc_iv;
165 	/* DMFC2 rt, 0x0202 (Set with DMTC2 rt, 0x1202) */
166 	unsigned long	cop2_crc_length;
167 	/* DMFC2 rt, 0x0200 (set with DMTC2 rt, 0x4200) */
168 	unsigned long	cop2_crc_poly;
169 	/* DMFC2 rt, 0x0402; DMFC2 rt, 0x040A */
170 	unsigned long	cop2_llm_dat[2];
171        /* DMFC2 rt, 0x0084 */
172 	unsigned long	cop2_3des_iv;
173 	/* DMFC2 rt, 0x0080; DMFC2 rt, 0x0081; DMFC2 rt, 0x0082 */
174 	unsigned long	cop2_3des_key[3];
175 	/* DMFC2 rt, 0x0088 (Set with DMTC2 rt, 0x0098) */
176 	unsigned long	cop2_3des_result;
177 	/* DMFC2 rt, 0x0111 (FIXME: Read Pass1 Errata) */
178 	unsigned long	cop2_aes_inp0;
179 	/* DMFC2 rt, 0x0102; DMFC2 rt, 0x0103 */
180 	unsigned long	cop2_aes_iv[2];
181 	/* DMFC2 rt, 0x0104; DMFC2 rt, 0x0105; DMFC2 rt, 0x0106; DMFC2
182 	 * rt, 0x0107 */
183 	unsigned long	cop2_aes_key[4];
184 	/* DMFC2 rt, 0x0110 */
185 	unsigned long	cop2_aes_keylen;
186 	/* DMFC2 rt, 0x0100; DMFC2 rt, 0x0101 */
187 	unsigned long	cop2_aes_result[2];
188 	/* DMFC2 rt, 0x0240; DMFC2 rt, 0x0241; DMFC2 rt, 0x0242; DMFC2
189 	 * rt, 0x0243; DMFC2 rt, 0x0244; DMFC2 rt, 0x0245; DMFC2 rt,
190 	 * 0x0246; DMFC2 rt, 0x0247; DMFC2 rt, 0x0248; DMFC2 rt,
191 	 * 0x0249; DMFC2 rt, 0x024A; DMFC2 rt, 0x024B; DMFC2 rt,
192 	 * 0x024C; DMFC2 rt, 0x024D; DMFC2 rt, 0x024E - Pass2 */
193 	unsigned long	cop2_hsh_datw[15];
194 	/* DMFC2 rt, 0x0250; DMFC2 rt, 0x0251; DMFC2 rt, 0x0252; DMFC2
195 	 * rt, 0x0253; DMFC2 rt, 0x0254; DMFC2 rt, 0x0255; DMFC2 rt,
196 	 * 0x0256; DMFC2 rt, 0x0257 - Pass2 */
197 	unsigned long	cop2_hsh_ivw[8];
198 	/* DMFC2 rt, 0x0258; DMFC2 rt, 0x0259 - Pass2 */
199 	unsigned long	cop2_gfm_mult[2];
200 	/* DMFC2 rt, 0x025E - Pass2 */
201 	unsigned long	cop2_gfm_poly;
202 	/* DMFC2 rt, 0x025A; DMFC2 rt, 0x025B - Pass2 */
203 	unsigned long	cop2_gfm_result[2];
204 	/* DMFC2 rt, 0x24F, DMFC2 rt, 0x50, OCTEON III */
205 	unsigned long	cop2_sha3[2];
206 };
207 #define COP2_INIT						\
208 	.cp2			= {0,},
209 
210 struct octeon_cvmseg_state {
211 	unsigned long cvmseg[CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE]
212 			    [cpu_dcache_line_size() / sizeof(unsigned long)];
213 };
214 
215 #elif defined(CONFIG_CPU_XLP)
216 struct nlm_cop2_state {
217 	u64	rx[4];
218 	u64	tx[4];
219 	u32	tx_msg_status;
220 	u32	rx_msg_status;
221 };
222 
223 #define COP2_INIT						\
224 	.cp2			= {{0}, {0}, 0, 0},
225 #else
226 #define COP2_INIT
227 #endif
228 
229 typedef struct {
230 	unsigned long seg;
231 } mm_segment_t;
232 
233 #ifdef CONFIG_CPU_HAS_MSA
234 # define ARCH_MIN_TASKALIGN	16
235 # define FPU_ALIGN		__aligned(16)
236 #else
237 # define ARCH_MIN_TASKALIGN	8
238 # define FPU_ALIGN
239 #endif
240 
241 struct mips_abi;
242 
243 /*
244  * If you change thread_struct remember to change the #defines below too!
245  */
246 struct thread_struct {
247 	/* Saved main processor registers. */
248 	unsigned long reg16;
249 	unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
250 	unsigned long reg29, reg30, reg31;
251 
252 	/* Saved cp0 stuff. */
253 	unsigned long cp0_status;
254 
255 #ifdef CONFIG_MIPS_FP_SUPPORT
256 	/* Saved fpu/fpu emulator stuff. */
257 	struct mips_fpu_struct fpu FPU_ALIGN;
258 	/* Assigned branch delay slot 'emulation' frame */
259 	atomic_t bd_emu_frame;
260 	/* PC of the branch from a branch delay slot 'emulation' */
261 	unsigned long bd_emu_branch_pc;
262 	/* PC to continue from following a branch delay slot 'emulation' */
263 	unsigned long bd_emu_cont_pc;
264 #endif
265 #ifdef CONFIG_MIPS_MT_FPAFF
266 	/* Emulated instruction count */
267 	unsigned long emulated_fp;
268 	/* Saved per-thread scheduler affinity mask */
269 	cpumask_t user_cpus_allowed;
270 #endif /* CONFIG_MIPS_MT_FPAFF */
271 
272 	/* Saved state of the DSP ASE, if available. */
273 	struct mips_dsp_state dsp;
274 
275 	/* Saved watch register state, if available. */
276 	union mips_watch_reg_state watch;
277 
278 	/* Other stuff associated with the thread. */
279 	unsigned long cp0_badvaddr;	/* Last user fault */
280 	unsigned long cp0_baduaddr;	/* Last kernel fault accessing USEG */
281 	unsigned long error_code;
282 	unsigned long trap_nr;
283 #ifdef CONFIG_CPU_CAVIUM_OCTEON
284 	struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128)));
285 	struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128)));
286 #endif
287 #ifdef CONFIG_CPU_XLP
288 	struct nlm_cop2_state cp2;
289 #endif
290 	struct mips_abi *abi;
291 };
292 
293 #ifdef CONFIG_MIPS_MT_FPAFF
294 #define FPAFF_INIT						\
295 	.emulated_fp			= 0,			\
296 	.user_cpus_allowed		= INIT_CPUMASK,
297 #else
298 #define FPAFF_INIT
299 #endif /* CONFIG_MIPS_MT_FPAFF */
300 
301 #ifdef CONFIG_MIPS_FP_SUPPORT
302 # define FPU_INIT						\
303 	.fpu			= {				\
304 		.fpr		= {{{0,},},},			\
305 		.fcr31		= 0,				\
306 		.msacsr		= 0,				\
307 	},							\
308 	/* Delay slot emulation */				\
309 	.bd_emu_frame = ATOMIC_INIT(BD_EMUFRAME_NONE),		\
310 	.bd_emu_branch_pc = 0,					\
311 	.bd_emu_cont_pc = 0,
312 #else
313 # define FPU_INIT
314 #endif
315 
316 #define INIT_THREAD  {						\
317 	/*							\
318 	 * Saved main processor registers			\
319 	 */							\
320 	.reg16			= 0,				\
321 	.reg17			= 0,				\
322 	.reg18			= 0,				\
323 	.reg19			= 0,				\
324 	.reg20			= 0,				\
325 	.reg21			= 0,				\
326 	.reg22			= 0,				\
327 	.reg23			= 0,				\
328 	.reg29			= 0,				\
329 	.reg30			= 0,				\
330 	.reg31			= 0,				\
331 	/*							\
332 	 * Saved cp0 stuff					\
333 	 */							\
334 	.cp0_status		= 0,				\
335 	/*							\
336 	 * Saved FPU/FPU emulator stuff				\
337 	 */							\
338 	FPU_INIT						\
339 	/*							\
340 	 * FPU affinity state (null if not FPAFF)		\
341 	 */							\
342 	FPAFF_INIT						\
343 	/*							\
344 	 * Saved DSP stuff					\
345 	 */							\
346 	.dsp			= {				\
347 		.dspr		= {0, },			\
348 		.dspcontrol	= 0,				\
349 	},							\
350 	/*							\
351 	 * saved watch register stuff				\
352 	 */							\
353 	.watch = {{{0,},},},					\
354 	/*							\
355 	 * Other stuff associated with the process		\
356 	 */							\
357 	.cp0_badvaddr		= 0,				\
358 	.cp0_baduaddr		= 0,				\
359 	.error_code		= 0,				\
360 	.trap_nr		= 0,				\
361 	/*							\
362 	 * Platform specific cop2 registers(null if no COP2)	\
363 	 */							\
364 	COP2_INIT						\
365 }
366 
367 struct task_struct;
368 
369 /* Free all resources held by a thread. */
370 #define release_thread(thread) do { } while(0)
371 
372 /*
373  * Do necessary setup to start up a newly executed thread.
374  */
375 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
376 
flush_thread(void)377 static inline void flush_thread(void)
378 {
379 }
380 
381 unsigned long get_wchan(struct task_struct *p);
382 
383 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
384 			 THREAD_SIZE - 32 - sizeof(struct pt_regs))
385 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
386 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
387 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
388 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
389 
390 /*
391  * Return_address is a replacement for __builtin_return_address(count)
392  * which on certain architectures cannot reasonably be implemented in GCC
393  * (MIPS, Alpha) or is unusable with -fomit-frame-pointer (i386).
394  * Note that __builtin_return_address(x>=1) is forbidden because GCC
395  * aborts compilation on some CPUs.  It's simply not possible to unwind
396  * some CPU's stackframes.
397  *
398  * __builtin_return_address works only for non-leaf functions.	We avoid the
399  * overhead of a function call by forcing the compiler to save the return
400  * address register on the stack.
401  */
402 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
403 
404 #ifdef CONFIG_CPU_HAS_PREFETCH
405 
406 #define ARCH_HAS_PREFETCH
407 #define prefetch(x) __builtin_prefetch((x), 0, 1)
408 
409 #define ARCH_HAS_PREFETCHW
410 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
411 
412 #endif
413 
414 /*
415  * Functions & macros implementing the PR_GET_FP_MODE & PR_SET_FP_MODE options
416  * to the prctl syscall.
417  */
418 extern int mips_get_process_fp_mode(struct task_struct *task);
419 extern int mips_set_process_fp_mode(struct task_struct *task,
420 				    unsigned int value);
421 
422 #define GET_FP_MODE(task)		mips_get_process_fp_mode(task)
423 #define SET_FP_MODE(task,value)		mips_set_process_fp_mode(task, value)
424 
425 #endif /* _ASM_PROCESSOR_H */
426